Possible Clues:

• United States Marine Band director from 1880 to 1892
• March composer whose name's last three letters are apt
• 'Manhattan Beach' composer
• 'The Liberty Bell' composer
• Composer of the operetta 'El Capitan'
• Master of march music
• March composer John Philip --
• John Philip --, American composer (1854-1932)
• Accordingly American embraces American composer
• Monty Python theme composer